A typical database system includes a database, such as a relational database, for storing and organizing data into one or more tables. Users of the database may send queries to the database system to retrieve data from more than one table according to specified criteria. Conventionally, a query may include a join operation that specifies a rule for combining two or more tables. But not every joined table is necessarily used by the database system to produce a result of the query. Therefore, a typical database system is inefficient because it may perform unnecessary joins, increasing query processing time and complexity.
In the drawings, like reference numbers generally indicate identical or similar elements. Additionally, generally, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears.